The present invention relates to a voltage monitoring module and a voltage monitoring system, and more specifically, to a voltage monitoring module and a voltage monitoring system for an assembled battery, for example.
With the recent widespread use of hybrid cars and electric vehicles, the number of vehicles incorporating batteries to obtain power from electric power is increasing. In such vehicles, an assembled battery having a configuration in which a number of battery cells are connected in series is generally used to obtain a high voltage. The voltage of each battery cell of the assembled battery varies depending on the status of use of the vehicle, as with gasoline for gasoline cars. For this reason, a system for monitoring the voltage is necessary to monitor the state of each battery cell.
A voltage monitoring module for monitoring a voltage of each battery cell has already been proposed (Japanese Unexamined Patent Application Publication No. 2009-257923). This voltage monitoring module has a function of detecting a disconnection by utilizing a voltage drop caused by a current flowing through a protection diode upon occurrence of a disconnection. In such a typical voltage monitoring module, disconnections between each of the battery cells, which are connected in series, and the voltage monitoring module are sequentially checked for each battery cell. The configuration of the voltage monitoring module and the method for detecting a disconnection will be described in detail later.